1. Field of the Invention
This invention relates to a camera which controls its diaphragm.
2. Description of the Related Art
Heretofore, in successive photographing operations in a single-lens reflex camera, a diaphragm of a photographing lens is returned to an open state and then moved to a predetermined stop value for every photographing operation. This operation is performed by maintaining a state in which the diaphragm of the photographing lens is mechanically charged by a spring and anchored in the open state, then releasing the anchorage in accordance with a shutter release, and controlling the diaphragm to move to a predetermined stop value. In the case of successive photographing operations, this operation is repeated even when the stop value after the second frame is identical to that for the first frame. Accordingly, time for returning the diaphragm of the photographing lens to the open state and time for controlling the diaphragm to move to a predetermined stop value are required. Hence, the successive photographing frame speed in successive photographing operations cannot be high, and power is wastefully consumed because energy is needed for charging and controlling the diaphragm. These facts are very inconvenient in a single-lens reflex camera, particularly in an AF (autofocusing) camera, for which a small size is required, because a considerable amount of electric power is needed for operating AF functions.